On the sensitivity of WCET estimates to the variability of basic blocks execution times
نویسندگان
چکیده
The Implicit Path Enumeration Technique (IPET) is a very popular approach to evaluate the Worst-Case Execution Time (WCET) of hard real-time applications. It computes the execution time of an execution path as the sum of the execution times of the basic blocks weighted by their respective execution counts. Several techniques to estimate the execution time of a block taking into account every possible prefix path have been proposed: the maximum value of the block execution time is then used for IPET calculation. The first purpose of this paper is to analyze the sensitivity of block execution times to prefix paths. Then we show how expanding the IPET model to consider the execution times related to different contexts for each basic block improves the accuracy of WCET estimates.
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